Keybind for auto-walk? Need some suggestions

I can't find a good keybind for auto-walk. I have used R for years (it's stupid I know), but thought it was about time to get rid of it. It took quite some time to get used to the new keybind alt+s, but now I manage to auto-walk if I backpeddle while using skills with scroll+modifier.

Got anny suggestions for a keybinding? I've got a razer naga mouse btw.

Edit: I'm using "<" now and it's working great. It's easy to reach and isn't causing any trouble :)